20-102338-Tacoma Smelter Plume Sampling Results Summary-06-12-2020-V1
1101 South Fawcett Avenue, Suite 200
Tacoma, Washington 98402
253.383.4940
June 12, 2020
Helix Design Group
6021 12th Street East, Suite 201
Tacoma, Washington 98424
Attention: Jeff Blachowski
Subject: Soil Sampling and Analytical Results Summary
Tacoma Smelter Plume Sampling
Lakehaven Water and Sewer District Maintenance Facility Improvements
Federal Way, Washington
File No. 4519-017-00
INTRODUCTION AND PROJECT UNDERSTANDING
GeoEngineers is pleased to present this letter summarizing the Tacoma Smelter Plume (TSP) soil sampling
activities performed at the Lakehaven Water and Sewer District Maintenance Facility (subject property)
located at 31627 1st Avenue South in Federal Way, Washington. The approximate project boundaries are
shown on the Vicinity Map, Figure 1. The overall project consists of demolition or modification of existing
buildings, construction of new buildings and associated site improvements. Ground disturbing activities are
anticipated as part of construction.
The subject property is located within the footprint of the area-wide contamination from the Tacoma Smelter
Plume (TSP) as mapped by the Washington State Department of Ecology (Ecology). Ecology’s map shows
where arsenic concentrations in surface/near surface soil have been predicted relative to the Ecology
Model Toxics Control Act (MTCA) Method A cleanup level for unrestricted land uses (ULU) of 20 milligrams
per kilogram (mg/kg). This information is made available to the public through Ecology’s Dirt Alert site at
https://fortress.wa.gov/ecy/dirtalert/. Arsenic is reported to be between 20 mg/kg and 40 mg/kg on the
subject property based on Ecology’s map of surface soil concentrations for arsenic. As a result, samples
are required to be collected for chemical analysis to characterize the soil from 0 to 6 inches below ground
surface (bgs) and 6 to 12 inches bgs and shall also include separate sampling of forest duff (where it is
located) in accordance with Ecology requirements.
Helix Design Group | June 12, 2020 Page 2
File No. 4519-017-00
METHODOLOGY
GeoEngineers prepared a field sampling plan for our staff including identifying sampling locations and
requirements that follows Ecology’s methodology identified in the Tacoma Smelter Plume Model Remedy
Guidance (TSPMRG) document dated June 2012. One decision unit (DU1) was selected for the site based
on the provided information that the entire proposed site is to be developed. The soil concentrations within
a decision unit are considered elevated if the average arsenic concentration is greater than 20 mg/kg and
the average lead concentration is greater than 250 mg/kg, or if any single sample has an arsenic
concentration greater than 40 mg/kg and/or a lead concentration greater than 500 mg/kg based on
information provided in the TSPMRG.
FIELD ACTIVITIES
Soil samples were collected at the subject property on February 11, 2020 for chemical analysis. Forty-one
soil samples were collected from 33 locations within DU1. Soil samples were collected using a
2-inch-diameter hand auger from 0 to 6 inches bgs at each of the 33 locations and from 6 to 12 inches bgs
at 8 of the 33 locations.
The sample locations are shown on the attached Site Plan, Figure 2. The soil samples were submitted for
chemical analysis for total arsenic and lead by United States Environmental Protection Agency (EPA)
Method 6010D. The analytical results are presented in Table 1 using the format identified in the Guidance.
The analytical laboratory report is provided in Appendix A.
CHEMICAL ANALYTICAL RESULTS
Arsenic was either not detected or was detected at concentrations less than the maximum concentration
(40 mg/kg) allowed under the TSPMRGD in the analyzed soil samples. The average arsenic concentration
was 6.4 mg/kg in the shallow soil samples and 5.7 mg/kg in the deep soil samples. This comparison
indicates the proposed development area falls below the “elevated” criteria and does not require
remediation under the TSPMRGD. Additionally, arsenic was not detected at concentrations greater than the
MTCA Method A ULU cleanup level (20 mg/kg) in the analyzed soil samples.
Lead was either not detected or was detected at concentrations less than the maximum concentration
(500 mg/kg) allowed under the TSPMRGD in the analyzed soil samples. The average lead concentration
was 15.4 mg/kg in the shallow soil samples and 11.4 mg/kg in the deep soil samples. This comparison
indicates the proposed development area falls below the “elevated” criteria and does not require
remediation under the TSPMRGD. Additionally, lead was not detected at concentrations greater than the
MTCA Method A ULU cleanup level (250 mg/kg) in the analyzed soil samples.
GeoEngineers coordinated a review with Eva Barber, Technical Assistance Coordinator for TSP program at
Ecology, regarding the soil sampling results in the areas of the planned improvements. In an email dated
April 7, 2020, Mrs. Barber requested that additional sampling be conducted within an area along the
southern portion of the property where topographic features and other subsurface explorations (completed
for our geotechnical study) identified an area of fill containing loose soil and layers of organic-rich soils,
interpreted to consist of on-site fill placed above topsoil and vegetation from previous site clearing and
grading activities. Mrs. Barber requested that the TSPMRG methods for stockpile sampling be followed to
Helix Design Group | June 12, 2020 Page 3
File No. 4519-017-00
evaluate the soil in this area and that sampling should extend down to the former native surface.
Mrs. Barber indicated that she will prepare a memorandum summarizing recommendations on how to
proceed with soil management following review of the soil analytical results.
CONCLUSIONS
The results of this investigation indicate arsenic and lead were detected at concentrations less than the
respective MTCA cleanup levels for ULU and the TSPMRG criteria with no single sample exceeding the
maximum concentrations of 40 mg/kg for arsenic and 500 mg/kg for lead. However, additional topography
review and subsurface exploration review completed at the subject property identified an area of fill
containing loose soil and layers of organic-rich soils, interpreted to consist of on-site materials placed as fill
above topsoil and vegetation from previous site clearing and grading activities. As a result, additional
testing, at depth, from this area will be required to satisfy Ecology’s TSPMRG requirements.
REFERENCES
Washington State Department of Ecology. 2012. “Tacoma Smelter Plume Model Remedies Guidance”
Toxics Cleanup Program Publication Number 12-09-086-A.
LIMITATIONS
We have prepared this report for Helix Design Group and the proposed Lakehaven Water and Sewer District
Maintenance Facility Improvements project in Federal Way, Washington. Helix Design Group may distribute
copies of this report to the owner, owner’s authorized agents and regulatory agencies as may be required
for the project.
Within the limitations of scope, schedule and budget, our services have been executed in accordance with
generally accepted environmental science practices in this area at the time this report was prepared. The
conclusions, recommendations, and opinions presented in this report are based on our professional
knowledge, judgment and experience. No warranty or other conditions, express or implied, should be
understood.
Please refer to Appendix B titled “Report Limitations and Guidelines for Use” for additional information
pertaining to use of this report.
Helix Design Group | June 12, 2020 Page 4
File No. 4519-017-00
We appreciate the opportunity to assist Helix Design Group with this project. Please call if you have
questions or require additional information.
Sincerely,
GeoEngineers, Inc.
Aaron M. Waggoner, LG, LHG Terry R. McPhetridge, LG, LHG
Project Geologist Principal
Stuart S. Thielman, PE Dennis J. (D.J.) Thompson P.E.
Geotechnical Engineer Associate
SST:AMW:TRM:tt:ch
Attachments:
Table 1. Chemical Analytical Data - Arsenic and Lead Concentrations in Soil
Figure 1. Vicinity Map
Figure 2. Site Plan
Appendix A – Laboratory Analytical Data
Appendix B – Report Limitations and Guidelines for Use
Disclaimer: Any electronic form, facsimile or hard copy of the original document (email, text, table, and/or figure), if provided, and any attachments are only a copy
of the original document. The original document is stored by GeoEngineers, Inc. and will serve as the official document of record.
DU
Sample
Number Soil Depth Date Time
Note: Corresponding
GeoEngineers Sample ID Arsenic
Average
Arsenic3 Lead
Average
Lead
1 1 2/11/20 0833 DU1-1-0-6 3.5 5.1
1 2 2/11/20 0837 DU1-2-0-6 5.7 8.1
1 3 2/11/20 0840 DU1-3-0-6 4.9 7.9
1 4 2/11/20 0842 DU1-4-0-6 7.4 12
1 5 2/11/20 0844 DU1-5-0-6 3.8 5.6
1 6 2/11/20 0847 DU1-6-0-6 3.1 U 9.1
1 7 2/11/20 0851 DU1-7-0-6 5.0 15
1 8 2/11/20 0853 DU1-8-0-6 3.0 5.7
1 9 2/11/20 0855 DU1-9-0-6 5.0 U 17
1 10 2/11/20 0859 DU1-10-0-6 5.8 14
1 11 2/11/20 0906 DU1-11-0-6 3.4 U 5.1
1 12 2/11/20 0916 DU1-12-0-6 4.3 14
1 13 2/11/20 0923 DU1-13-0-6 5.3 11
1 14 2/11/20 0932 DU1-14-0-6 2.8 U 5.9
1 15 2/11/20 0940 DU1-15-0-6 3.0 U 8.3
1 16 2/11/20 0946 DU1-16-0-6 3.9 11
1 17 2/11/20 0955 DU1-17-0-6 3.0 U 6.8
1 18 2/11/20 0957 DU1-18-0-6 18 35
1 19 2/11/20 1001 DU1-19-0-6 11 25
1 20 2/11/20 1038 DU1-20-0-6 3.2 U 5.5
1 21 2/11/20 1044 DU1-21-0-6 5.5 7.9
1 22 2/11/20 1046 DU1-22-0-6 3.6 5.5
1 23 2/11/20 1048 DU1-23-0-6 3.7 5.4
1 24 2/11/20 1322 DU1-24-0-6 20 55
1 25 2/11/20 1324 DU1-25-0-6 6.8 15
1 26 2/11/20 1326 DU1-26-0-6 7.8 19
1 27 2/11/20 1329 DU1-27-0-6 8.4 20
1 28 2/11/20 1332 DU1-28-0-6 13 22
1 29 2/11/20 1336 DU1-29-0-6 11 46
1 30 2/11/20 1340 DU1-30-0-6 7.2 4.5
1 31 2/11/20 1409 DU1-31-0-6 15 49
1 32 2/11/20 1427 DU1-32-0-6 11 24
1 33 1445 DU1-33-0-6 3.3 6.7
615
Federal Way, Washington
Lakehaven Water & Sewer District Maintenance Facility Improvements
Chemical Analytical Data - Arsenic and Lead Concentrations1 in Soil
Table 1
Property Address: 31627 1st Avenue South, Federal Way, WA 98003 Testing Parameters2
(mg/kg)Sampled By: GeoEngineers
File No. 4519-017-00
Table 1 | June 12, 2020 Page 1 of 2
2/11/20
DU
Sample
Number Soil Depth Date Time
Note: Corresponding
GeoEngineers Sample ID Arsenic
Average
Arsenic3 Lead
Average
Lead
1 1 2/11/20 0834 DU1-1-6-12 4.9 6.3
1 11 2/11/20 0907 DU1-11-6-12 2.7 U 2.7 U
1 13 2/11/20 0925 DU1-13-6-12 5.9 9.8
1 16 2/11/20 0948 DU1-16-6-12 3.9 13
1 19 2/11/20 1004 DU1-19-6-12 7.7 20
1 20 2/11/20 1040 DU1-20-6-12 2.9 U 2.9 U
1 29 2/11/20 1337 DU1-29-6-12 16 35
1 31 2/11/20 1410 DU1-31-6-12 4.4 4.6
20 N/A 250 N/A
40 20 500 250
Notes:
ULU = Unrestricted Land Use DU = Decision Unit
MTCA = Model Toxics Control Act mg/kg = milligram per kilogram
TSPMRG = Tacoma Smelter Plume Model Remedy Guidance U = not detected at the laboratory reporting limit
N/A = Not Applicable
Bold = Analyte detected greater than the laboratory reporting limit
Gray Shaded = Analyte detected greater than the corresponding MTCA Method A Cleanup Levels; Arsenic >20 mg/kg, Lead >250 mg/kg
3 Non-detects are assigned a value equal to half the laboratory detection limit for the purpose of calculating the average concentration within a decision
unit.
1 Chemical analysis was performed by OnSite Environmental, Inc., of Redmond, Washington.
2 Metals analyzed by United States Environmental Protection Agency (EPA) Method 6010D.
MTCA Method A ULU Cleanup Levels
TSPMRG Maximum Criteria
6-12 6 11
File No. 4519-017-00
Table 1 | June 12, 2020 Page 2 of 2
μ
SITE
Vicinity Map
Figure 1
Lakehaven Water & Sewer District
Maintenance Facility Improvements
Federal Way, Washington
2,000 2,0000
Feet
Data Source: Mapbox Open Street Map, 2016
Notes:
1. The locations of all features shown are approximate.
2. This drawing is for information purposes. It is intended to assist in
showing features discussed in an attached document. GeoEngineers, Inc.
cannot guarantee the accuracy and content of electronic files. The master
file is stored by GeoEngineers, Inc. and will serve as the official record of
this communication.
Projection: NAD 1983 UTM Zone 10N
P:\4\4519017\GIS\MXD\451901700_F01_VicinityMap.mxd Date Exported: 02/14/20 by mwoods
Parcel 1
Parcel 3
1st Ave S
Parcel 2
DU1-1
DU1-2
DU1-3
DU1-4 DU1-5
DU1-6
DU1-7
DU1-8 DU1-9
DU1-10
DU1-11
DU1-12
DU1-13
DU1-14
DU1-15
DU1-16
DU1-17DU1-18DU1-19
DU1-20
DU1-21
DU1-22
DU1-23
DU1-24DU1-25DU1-26
DU1-27
DU1-28
DU1-29
DU1-30
DU1-31
DU1-32
DU1-33
DU1
Figure 2
Lakehaven Water & Sewer District
Maintenance Facility Improvements
Federal Way, Washington
Tacoma Smelter Plume
Sample Map
\\geoengineers.com\WAN\Projects\4\4519017\CAD\00\Environmental\451901700_F02_Site Plan.dwg TAB:F02 Date Exported: 03/16/20 - 10:00 by mwoodsNotes:
1. The locations of all features shown are approximate.
2. This drawing is for information purposes. It is intended to assist in showing
features discussed in an attached document. GeoEngineers, Inc. cannot
guarantee the accuracy and content of electronic files. The master file is stored
by GeoEngineers, Inc. and will serve as the official record of this communication.
Data Source: Aerial from Google Earth Pro dated 7/1/2018.
Projection: NAD83 Washington State Planes, North Zone, US Foot
Feet
080 80
Legend
Site Boundary
0" to 6" Sample Location
0" to 6" and 6" to 12" Sample Location
DU1-02
DU1-01
Existing Asphalt Pavement
Decision Unit BoundaryDU1
APPENDIX A
Laboratory Analytical Data
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
February 24, 2020
Stuart Thielmann
GeoEngineers, Inc.
1101 Fawcett Avenue South, Unit 200
Tacoma, WA 98402
Re: Analytical Data for Project 4519-017-00
Laboratory Reference No. 2002-142
Dear Stuart:
Enclosed are the analytical results and associated quality control data for samples submitted on February 13, 2020.
The standard policy of OnSite Environmental, Inc. is to store your samples for 30 days from the date of receipt. If you
require longer storage, please contact the laboratory.
We appreciate the opportunity to be of service to you on this project. If you have any questions concerning the data,
or need additional information, please feel free to call me.
Sincerely,
David Baumeister
Project Manager
Enclosures
2
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
Case Narrative
Samples were collected on February 11, 2020 and received by the laboratory on February 13, 2020. They were
maintained at the laboratory at a temperature of 2oC to 6oC.
Please note that any and all soil sample results are reported on a dry-weight basis, unless otherwise noted below.
General QA/QC issues associated with the analytical data enclosed in this laboratory report will be indicated with a
reference to a comment or explanation on the Data Qualifier page. More complex and involved QA/QC issues will be
discussed in detail below.
3
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
ANALYTICAL REPORT FOR SAMPLES
Client ID Laboratory ID Matrix Date Sampled Date Received Notes
DU1-1-0-6 02-142-01 Soil 2-11-20 2-13-20
DU1-1-6-12 02-142-02 Soil 2-11-20 2-13-20
DU1-2-0-6 02-142-03 Soil 2-11-20 2-13-20
DU1-3-0-6 02-142-04 Soil 2-11-20 2-13-20
DU1-4-0-6 02-142-05 Soil 2-11-20 2-13-20
DU1-5-0-6 02-142-06 Soil 2-11-20 2-13-20
DU1-6-0-6 02-142-07 Soil 2-11-20 2-13-20
DU1-7-0-6 02-142-08 Soil 2-11-20 2-13-20
DU1-8-0-6 02-142-09 Soil 2-11-20 2-13-20
DU1-9-0-6 02-142-10 Soil 2-11-20 2-13-20
DU1-10-0-6 02-142-11 Soil 2-11-20 2-13-20
DU1-11-0-6 02-142-12 Soil 2-11-20 2-13-20
DU1-11-6-12 02-142-13 Soil 2-11-20 2-13-20
DU1-12-0-6 02-142-14 Soil 2-11-20 2-13-20
DU1-13-0-6 02-142-15 Soil 2-11-20 2-13-20
DU1-13-6-12 02-142-16 Soil 2-11-20 2-13-20
DU1-14-0-6 02-142-17 Soil 2-11-20 2-13-20
DU1-15-0-6 02-142-18 Soil 2-11-20 2-13-20
DU1-16-0-6 02-142-19 Soil 2-11-20 2-13-20
DU1-16-6-12 02-142-20 Soil 2-11-20 2-13-20
DU1-17-0-6 02-142-21 Soil 2-11-20 2-13-20
DU1-18-0-6 02-142-22 Soil 2-11-20 2-13-20
DU1-19-0-6 02-142-23 Soil 2-11-20 2-13-20
DU1-19-6-12 02-142-24 Soil 2-11-20 2-13-20
DU1-20-0-6 02-142-25 Soil 2-11-20 2-13-20
DU1-20-6-12 02-142-26 Soil 2-11-20 2-13-20
DU1-21-0-6 02-142-27 Soil 2-11-20 2-13-20
DU1-22-0-6 02-142-28 Soil 2-11-20 2-13-20
DU1-23-0-6 02-142-29 Soil 2-11-20 2-13-20
4
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
ANALYTICAL REPORT FOR SAMPLES
Client ID Laboratory ID Matrix Date Sampled Date Received Notes
DU1-24-0-6 02-142-30 Soil 2-11-20 2-13-20
DU1-25-0-6 02-142-31 Soil 2-11-20 2-13-20
DU1-26-0-6 02-142-32 Soil 2-11-20 2-13-20
DU1-27-0-6 02-142-33 Soil 2-11-20 2-13-20
DU1-28-0-6 02-142-34 Soil 2-11-20 2-13-20
DU1-29-0-6 02-142-35 Soil 2-11-20 2-13-20
DU1-29-6-12 02-142-36 Soil 2-11-20 2-13-20
DU1-30-0-6 02-142-37 Soil 2-11-20 2-13-20
DU1-31-0-6 02-142-38 Soil 2-11-20 2-13-20
DU1-31-6-12 02-142-39 Soil 2-11-20 2-13-20
DU1-32-0-6 02-142-40 Soil 2-11-20 2-13-20
DU1-33-0-6 02-142-41 Soil 2-11-20 2-13-20
5
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-1-0-6
Laboratory ID: 02-142-01
Arsenic 3.5 3.3 EPA 6020B 2-18-20 2-20-20
Lead 5.1 3.3 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-1-6-12
Laboratory ID: 02-142-02
Arsenic 4.9 3.2 EPA 6020B 2-18-20 2-20-20
Lead 6.3 3.2 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-2-0-6
Laboratory ID: 02-142-03
Arsenic 5.7 3.1 EPA 6020B 2-18-20 2-20-20
Lead 8.1 3.1 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-3-0-6
Laboratory ID: 02-142-04
Arsenic 4.9 3.2 EPA 6020B 2-18-20 2-20-20
Lead 7.9 3.2 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-4-0-6
Laboratory ID: 02-142-05
Arsenic 7.4 3.2 EPA 6020B 2-18-20 2-20-20
Lead 12 3.2 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-5-0-6
Laboratory ID: 02-142-06
Arsenic 3.8 2.9 EPA 6020B 2-18-20 2-20-20
Lead 5.6 2.9 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-6-0-6
Laboratory ID: 02-142-07
Arsenic ND 3.1 EPA 6020B 2-18-20 2-20-20
Lead 9.1 3.1 EPA 6020B 2-18-20 2-20-20
6
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-7-0-6
Laboratory ID: 02-142-08
Arsenic 5.0 3.5 EPA 6020B 2-18-20 2-20-20
Lead 15 3.5 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-8-0-6
Laboratory ID: 02-142-09
Arsenic 3.0 2.8 EPA 6020B 2-18-20 2-20-20
Lead 5.7 2.8 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-9-0-6
Laboratory ID: 02-142-10
Arsenic ND 5.0 EPA 6020B 2-18-20 2-20-20
Lead 17 5.0 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-10-0-6
Laboratory ID: 02-142-11
Arsenic 5.8 3.6 EPA 6020B 2-18-20 2-20-20
Lead 14 3.6 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-11-0-6
Laboratory ID: 02-142-12
Arsenic ND 3.4 EPA 6020B 2-18-20 2-20-20
Lead 5.1 3.4 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-11-6-12
Laboratory ID: 02-142-13
Arsenic ND 2.7 EPA 6020B 2-18-20 2-20-20
Lead ND 2.7 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-12-0-6
Laboratory ID: 02-142-14
Arsenic 4.3 3.0 EPA 6020B 2-18-20 2-20-20
Lead 14 3.0 EPA 6020B 2-18-20 2-20-20
7
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-13-0-6
Laboratory ID: 02-142-15
Arsenic 5.3 3.3 EPA 6020B 2-18-20 2-20-20
Lead 11 3.3 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-13-6-12
Laboratory ID: 02-142-16
Arsenic 5.9 2.9 EPA 6020B 2-18-20 2-20-20
Lead 9.8 2.9 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-14-0-6
Laboratory ID: 02-142-17
Arsenic ND 2.8 EPA 6020B 2-18-20 2-20-20
Lead 5.9 2.8 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-15-0-6
Laboratory ID: 02-142-18
Arsenic ND 3.0 EPA 6020B 2-18-20 2-20-20
Lead 8.3 3.0 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-16-0-6
Laboratory ID: 02-142-19
Arsenic 3.9 2.9 EPA 6020B 2-18-20 2-20-20
Lead 11 2.9 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-16-6-12
Laboratory ID: 02-142-20
Arsenic 4.0 3.2 EPA 6020B 2-18-20 2-20-20
Lead 13 3.2 EPA 6020B 2-18-20 2-20-20
Client ID: DU1-17-0-6
Laboratory ID: 02-142-21
Arsenic ND 3.0 EPA 6020B 2-19-20 2-20-20
Lead 6.8 3.0 EPA 6020B 2-19-20 2-20-20
8
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-18-0-6
Laboratory ID: 02-142-22
Arsenic 18 3.6 EPA 6020B 2-19-20 2-20-20
Lead 35 3.6 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-19-0-6
Laboratory ID: 02-142-23
Arsenic 11 3.4 EPA 6020B 2-19-20 2-20-20
Lead 25 3.4 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-19-6-12
Laboratory ID: 02-142-24
Arsenic 7.7 3.2 EPA 6020B 2-19-20 2-20-20
Lead 20 3.2 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-20-0-6
Laboratory ID: 02-142-25
Arsenic ND 3.2 EPA 6020B 2-19-20 2-20-20
Lead 5.5 3.2 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-20-6-12
Laboratory ID: 02-142-26
Arsenic ND 2.9 EPA 6020B 2-19-20 2-20-20
Lead ND 2.9 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-21-0-6
Laboratory ID: 02-142-27
Arsenic 5.5 3.1 EPA 6020B 2-19-20 2-20-20
Lead 7.9 3.1 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-22-0-6
Laboratory ID: 02-142-28
Arsenic 3.6 3.2 EPA 6020B 2-19-20 2-20-20
Lead 5.5 3.2 EPA 6020B 2-19-20 2-20-20
9
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-23-0-6
Laboratory ID: 02-142-29
Arsenic 3.7 3.1 EPA 6020B 2-19-20 2-20-20
Lead 5.4 3.1 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-24-0-6
Laboratory ID: 02-142-30
Arsenic 20 4.1 EPA 6020B 2-19-20 2-20-20
Lead 55 4.1 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-25-0-6
Laboratory ID: 02-142-31
Arsenic 6.8 3.6 EPA 6020B 2-19-20 2-20-20
Lead 15 3.6 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-26-0-6
Laboratory ID: 02-142-32
Arsenic 7.8 3.3 EPA 6020B 2-19-20 2-20-20
Lead 19 3.3 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-27-0-6
Laboratory ID: 02-142-33
Arsenic 8.4 3.3 EPA 6020B 2-19-20 2-20-20
Lead 20 3.3 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-28-0-6
Laboratory ID: 02-142-34
Arsenic 13 3.2 EPA 6020B 2-19-20 2-20-20
Lead 22 3.2 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-29-0-6
Laboratory ID: 02-142-35
Arsenic 11 4.9 EPA 6020B 2-19-20 2-20-20
Lead 46 4.9 EPA 6020B 2-19-20 2-20-20
10
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
Client ID: DU1-29-6-12
Laboratory ID: 02-142-36
Arsenic 16 4.3 EPA 6020B 2-19-20 2-20-20
Lead 35 4.3 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-30-0-6
Laboratory ID: 02-142-37
Arsenic 7.2 3.1 EPA 6020B 2-19-20 2-20-20
Lead 4.5 3.1 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-31-0-6
Laboratory ID: 02-142-38
Arsenic 15 5.0 EPA 6020B 2-19-20 2-20-20
Lead 49 5.0 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-31-6-12
Laboratory ID: 02-142-39
Arsenic 4.4 3.1 EPA 6020B 2-19-20 2-20-20
Lead 4.6 3.1 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-32-0-6
Laboratory ID: 02-142-40
Arsenic 11 3.8 EPA 6020B 2-19-20 2-20-20
Lead 24 3.8 EPA 6020B 2-19-20 2-20-20
Client ID: DU1-33-0-6
Laboratory ID: 02-142-41
Arsenic 3.3 0.64 EPA 6020B 2-21-20 2-21-20
Lead 6.7 0.64 EPA 6020B 2-21-20 2-21-20
11
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
QUALITY CONTROL
Matrix: Soil
Units: mg/Kg (ppm)
Date Date
Analyte Result PQL Method Prepared Analyzed Flags
METHOD BLANK
Laboratory ID: MB0218SM2
Arsenic ND 2.5 EPA 6020B 2-18-20 2-20-20
Lead ND 2.5 EPA 6020B 2-18-20 2-20-20
Laboratory ID: MB0219SM1
Arsenic ND 2.5 EPA 6020B 2-19-20 2-20-20
Lead ND 2.5 EPA 6020B 2-19-20 2-20-20
Laboratory ID: MB0221SM1
Arsenic ND 2.5 EPA 6020B 2-21-20 2-21-20
Lead ND 2.5 EPA 6020B 2-21-20 2-21-20
12
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
TOTAL METALS
EPA 6020B
QUALITY CONTROL
Matrix: Soil
Units: mg/Kg (ppm)
Source Percent Recovery RPD
Analyte Result Spike Level Result Recovery Limits RPD Limit Flags
DUPLICATE
Laboratory ID: 02-142-01
ORIG DUP
Arsenic 2.64 2.63 NA NA NA NA 0 20
Lead 3.88 3.79 NA NA NA NA 2 20
Laboratory ID: 02-142-21
ORIG DUP
Arsenic ND ND NA NA NA NA NA 20
Lead 5.61 6.30 NA NA NA NA 12 20
Laboratory ID: 02-142-41
ORIG DUP
Arsenic 12.8 10.5 NA NA NA NA 19 20
Lead 26.3 24.9 NA NA NA NA 5 20
MATRIX SPIKES
Laboratory ID: 02-142-01
MS MSD MS MSD MS MSD
Arsenic 91.5 92.0 100 100 2.64 89 89 75-125 1 20
Lead 221 222 250 250 3.88 87 87 75-125 0 20
Laboratory ID: 02-142-21
MS MSD MS MSD MS MSD
Arsenic 91.5 93.5 100 100 2.08 89 91 75-125 2 20
Lead 222 233 250 250 5.61 87 91 75-125 5 20
Laboratory ID: 02-142-41
MS MSD MS MSD MS MSD
Arsenic 97.5 98.0 100 100 12.8 85 85 75-125 1 20
Lead 247 249 250 250 26.3 88 89 75-125 1 20
13
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
% MOISTURE
Date
Client ID Lab ID % Moisture Analyzed
DU1-1-0-6 02-142-01 24 2-14-20
DU1-1-6-12 02-142-02 22 2-14-20
DU1-2-0-6 02-142-03 20 2-14-20
DU1-3-0-6 02-142-04 21 2-14-20
DU1-4-0-6 02-142-05 23 2-14-20
DU1-5-0-6 02-142-06 15 2-14-20
DU1-6-0-6 02-142-07 21 2-14-20
DU1-7-0-6 02-142-08 29 2-14-20
DU1-8-0-6 02-142-09 12 2-14-20
DU1-9-0-6 02-142-10 50 2-14-20
DU1-10-0-6 02-142-11 30 2-14-20
DU1-11-0-6 02-142-12 26 2-14-20
DU1-11-6-12 02-142-13 8 2-14-20
DU1-12-0-6 02-142-14 17 2-14-20
DU1-13-0-6 02-142-15 24 2-14-20
DU1-13-6-12 02-142-16 15 2-14-20
DU1-14-0-6 02-142-17 12 2-14-20
DU1-15-0-6 02-142-18 17 2-14-20
DU1-16-0-6 02-142-19 13 2-14-20
DU1-16-6-12 02-142-20 21 2-14-20
DU1-17-0-6 02-142-21 18 2-14-20
DU1-18-0-6 02-142-22 30 2-14-20
DU1-19-0-6 02-142-23 25 2-14-20
DU1-19-6-12 02-142-24 21 2-14-20
DU1-20-0-6 02-142-25 21 2-14-20
DU1-20-6-12 02-142-26 13 2-14-20
DU1-21-0-6 02-142-27 20 2-14-20
14
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Date of Report: February 24, 2020
Samples Submitted: February 13, 2020
Laboratory Reference: 2002-142
Project: 4519-017-00
% MOISTURE
Date
Client ID Lab ID % Moisture Analyzed
DU1-22-0-6 02-142-28 22 2-14-20
DU1-23-0-6 02-142-29 20 2-14-20
DU1-24-0-6 02-142-30 39 2-14-20
DU1-25-0-6 02-142-31 31 2-14-20
DU1-26-0-6 02-142-32 23 2-14-20
DU1-27-0-6 02-142-33 24 2-14-20
DU1-28-0-6 02-142-34 23 2-14-20
DU1-29-0-6 02-142-35 49 2-14-20
DU1-29-6-12 02-142-36 41 2-14-20
DU1-30-0-6 02-142-37 19 2-14-20
DU1-31-0-6 02-142-38 50 2-14-20
DU1-31-6-12 02-142-39 20 2-14-20
DU1-32-0-6 02-142-40 35 2-14-20
DU1-33-0-6 02-142-41 22 2-14-20
15
OnSite Environmental, Inc. 14648 NE 95th Street, Redmond, WA 98052 (425) 883-3881
This report pertains to the samples analyzed in accordance with the chain of custody,
and is intended only for the use of the individual or company to whom it is addressed.
Data Qualifiers and Abbreviations A - Due to a high sample concentration, the amount spiked is insufficient for meaningful MS/MSD recovery data. B - The analyte indicated was also found in the blank sample. C - The duplicate RPD is outside control limits due to high result variability when analyte concentrations are within five times the quantitation limit. E - The value reported exceeds the quantitation range and is an estimate. F - Surrogate recovery data is not available due to the high concentration of coeluting target compounds. H - The analyte indicated is a common laboratory solvent and may have been introduced during sample preparation, and be impacting the sample result. I - Compound recovery is outside of the control limits. J - The value reported was below the practical quantitation limit. The value is an estimate. K - Sample duplicate RPD is outside control limits due to sample inhomogeneity. The sample was re-extracted and re-analyzed with similar results. L - The RPD is outside of the control limits. M - Hydrocarbons in the gasoline range are impacting the diesel range result. M1 - Hydrocarbons in the gasoline range (toluene-naphthalene) are present in the sample. N - Hydrocarbons in the lube oil range are impacting the diesel range result. N1 - Hydrocarbons in diesel range are impacting lube oil range results. O - Hydrocarbons indicative of heavier fuels are present in the sample and are impacting the gasoline result. P - The RPD of the detected concentrations between the two columns is greater than 40. Q - Surrogate recovery is outside of the control limits. S - Surrogate recovery data is not available due to the necessary dilution of the sample. T - The sample chromatogram is not similar to a typical ____________. U - The analyte was analyzed for, but was not detected above the reported sample quantitation limit. U1 - The practical quantitation limit is elevated due to interferences present in the sample. V - Matrix Spike/Matrix Spike Duplicate recoveries are outside control limits due to matrix effects. W - Matrix Spike/Matrix Spike Duplicate RPD are outside control limits due to matrix effects. X - Sample extract treated with a mercury cleanup procedure.
X1- Sample extract treated with a sulfuric acid/silica gel cleanup procedure.
Y - The calibration verification for this analyte exceeded the 20% drift specified in methods 8260 & 8270, and
therefore the reported result should be considered an estimate. The overall performance of the calibration
verification standard met the acceptance criteria of the method. Z - ND - Not Detected at PQL
PQL - Practical Quantitation Limit
RPD - Relative Percent Difference
APPENDIX B
Report Limitations and Guidelines for Use
Helix Design Group | June 12, 2020 Page B-1
File No. 4519-017-00
APPENDIX B
REPORT LIMITATIONS AND GUIDELINES FOR USE 1
This appendix provides information to help you manage your risks with respect to the use of this report.
Please confer with GeoEngineers if you need to know more about how these “Report Limitations and
Guidelines for Use” apply to your project or property.
Read These Provisions Closely
It is important to recognize that environmental engineering and geoscience practices (geotechnical
engineering, geology and environmental science) are less exact than other engineering and natural science
disciplines. GeoEngineers includes these explanatory “limitations” provisions in our reports to help reduce
the risk of misunderstandings or unrealistic expectations that lead to disappointments, claims and
disputes.
Environmental Services Are Performed for Specific Purposes, Persons and Projects
GeoEngineers has prepared this Soil Sampling and Analytical Results Summary for the proposed
Lakehaven Water and Sewer District Maintenance Facility Improvements project in Federal Way,
Washington in general accordance with the scope and limitations of our proposal, dated September 19,
2019. This report has been prepared for the exclusive use of Helix Design Group. This report is not intended
for use by others, and the information contained herein is not applicable to other properties.
GeoEngineers structures its services to meet the specific needs of its clients. For example, an ESA study
conducted for a property owner may not fulfill the needs of a prospective purchaser of the same property.
Because each environmental study is unique, each environmental report is unique, prepared solely for the
specific client and property. Use of this report is not recommended for any purpose or project other than as
expressly stated in this report.
This Environmental Report is Based on a Unique Set of Project-Specific Factors
This report has been prepared for the proposed Lakehaven Water and Sewer District Maintenance Facility
Improvements project in Federal Way, Washington. GeoEngineers considered a number of unique, project-
specific factors when establishing the scope of services for this Project. Unless GeoEngineers specifically
indicates otherwise, it is important not to rely on this report if it was:
■ not prepared for you,
■ not prepared for your Project,
■ not prepared for the specific site explored, or
■ completed before Project changes were made.
1 Developed based on material provided by GBA, GeoProfessional Business Association; www.geoprofessional.org.
Helix Design Group | June 12, 2020 Page B-2
File No. 4519-017-00
If changes to the Project or property occur after the date of this report, GeoEngineers cannot be responsible
for any consequences of such changes in relation to this report unless we have been given the opportunity
to review our interpretations and recommendations in the context of such changes. Based on that review,
we can provide written modifications or confirmation, as appropriate.
Reliance Conditions for Third Parties
This report was prepared for the exclusive use of the party(ies) to whom this report is addressed. No other
party may rely on the product of our services unless we agree to such reliance in advance and in writing.
Within the limitations of the agreed Project scope, schedule and budget, our services have been executed
in accordance with our Agreement with the Client and generally accepted environmental practices in this
area at the time this report was prepared.
Understand That Geotechnical Issues Have Not Been Addressed
Unless geotechnical engineering was specifically included in our scope of service, this report does not
provide any geotechnical findings, conclusions, or recommendations, including but not limited to, the
suitability of subsurface materials for construction purposes.
Do Not Separate Documentation from the Report
Environmental reports often include supplemental documentation, such as maps, figures and table. Do not
separate such documentation from the report. Further, do not, and do not permit any other party to redraw
or modify any of the supplemental documentation for incorporation into other professionals’ instruments
of service.
Environmental Regulations Change and Evolve
Some substances may be present in the vicinity of the subject property in quantities or under conditions
that may have led, or may lead, to contamination of the subject property, but are not included in current
local, state or federal regulatory definitions of hazardous substances or do not otherwise present current
potential liability. GeoEngineers cannot be responsible if the standards for appropriate inquiry, or regulatory
definitions of hazardous substances, change or if more stringent environmental standards are developed
in the future.
Uncertainty May Remain Even After This Phase II ESA is Completed
Performance of a Phase II ESA is intended to reduce uncertainty regarding the potential for contamination
in connection with a property, but no ESA can wholly eliminate that uncertainty. Our interpretation of
subsurface conditions in this study is based on field observations and chemical analytical data from widely
spaced sampling locations. It is always possible that contamination exists in areas that were not explored,
sampled or analyzed.
Subsurface Conditions Can Change
This environmental report is based on conditions that existed at the time the study was performed. The
findings and conclusions of this report may be affected by the passage of time, by man-made events such
as construction on or adjacent to the subject property, by new releases of hazardous substances, new
information or technology that become available subsequent to the report date, or by natural events such
as floods, earthquakes, slope instability or groundwater fluctuations. Please contact GeoEngineers before
Helix Design Group | June 12, 2020 Page B-3
File No. 4519-017-00
applying this report for its intended purpose so that GeoEngineers may evaluate whether changed
conditions affect the continued applicability of the report.
Soil and Groundwater End Use
The cleanup levels referenced in this report are site- and situation-specific. The cleanup levels may not be
applicable for other properties or for other on-site uses of the affected soil and/or groundwater. Note that
hazardous substances may be present in some of the on-site soil and/or groundwater at detectable
concentrations that are less than the referenced cleanup levels. GeoEngineers should be contacted prior
to the export of soil or groundwater from the subject property or reuse of the affected soil or groundwater
on-site to evaluate the potential for associated environmental liabilities. GeoEngineers will not assume
responsibility for potential environmental liability arising out of the transfer of soil and/or groundwater from
the subject property to another location, or the reuse of such soil and/or groundwater on-site in any
instances that we did not recommend, know of, or control.
Most Environmental Findings Are Professional Opinions
Our interpretations of subsurface conditions are based on field observations and chemical analytical data
from widely spaced sampling locations at the subject property. Site exploration identifies subsurface
conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers
reviewed field and laboratory data and then applied its professional judgment to render an informed opinion
about subsurface conditions throughout the property. Actual subsurface conditions may differ significantly
from those indicated in this report. Our report, conclusions and interpretations should not be construed as
a warranty of the subsurface conditions.
Biological Pollutants
GeoEngineers’ Scope of Work specifically excludes the investigation, detection, prevention or assessment
of the presence of Biological Pollutants. Accordingly, this report does not include any interpretations,
recommendations, findings or conclusions regarding the detecting, assessing, preventing or abating of
Biological Pollutants, and no conclusions or inferences should be drawn regarding Biological Pollutants as
they may relate to this Project. The term “Biological Pollutants” includes, but is not limited to, molds, fungi,
spores, bacteria and viruses, and/or any of their byproducts.
A Client that desires these specialized services is advised to obtain them from a consultant who offers
services in this specialized field.
Information Provided by Others
GeoEngineers has relied upon certain data or information provided or compiled by others in the
performance of our services. Although we use sources that we reasonably believe to be trustworthy,
GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or
compiled by others.